This invention relates in general to welding methods and devices and in particular to a new and useful method of welding a tube bend in which a tube bend wall is built of a plurality of sections and to an apparatus for effecting the welding method.
Deposit welding or built-up welding has been employed at a growing rate for manufacturing large and high quality workpieces, particularly for parts of nuclear reactors. For example, the German OS No. 26 29 571 discloses a method of manufacturing semi-donut shaped shells which are made up of sections of equal bent angles which are welded to a bend by means of longitudinal seams extending in the plane of the bend. Even though the welded semi-donut shells have advantages over cast or forged ones in their structural condition, strength properties, and manufacturing costs, the longitudinal seams needed in the manufacturing process are to be considered disadvantageous. Another disadvantage of this prior art method is that only one welding head can be employed, so that no simultaneous inside plating of the wall of the bend, which is frequently necessary, is possible. It is further known in built-up welding, to employ welding heads which are rotatable about the vertical axis (German AS No. 24 00 916).